The revelation contradicts AEG Live's defense that it did not hire or pay the doctor convicted in Jackson's death.

"To me, it's a mistake," AEG Live Senor Vice President and General Counsel Shawn Trell said when confronted with a letter sent to Jackson's estate.

Trell, testifying Monday in the Michael Jackson wrongful death trial, also said his company's chief financial officer made another major error by classifying Dr. Murray's fees as "production costs" and not "advances" in all of the budgets for Jackson's "This It It" tour.

"Mistakenly, yes," Trell said.

Photos:Who's who in Jackson trial

Photos:Who's who in Jackson trial

Key players in Jackson wrongful death trial – Katherine Jackson: Michael's mother, 82, was deposed for nine hours over three days by AEG Live lawyers. As the guardian of her son's three children, she is a plaintiff in the wrongful death lawsuit against the company that promoted Michael Jackson's comeback concerts.

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Photos:Who's who in Jackson trial

Key players in Jackson wrongful death trial – Kenny Ortega: He was chosen by Michael Jackson and AEG Live to direct and choreograph the "This Is It" shows. Ortega, who choreographed for Jackson's "Dangerous" and "HIStory" tours, testified at Dr. Conrad Murray's criminal trial that "Jackson was frail" at a rehearsal days before his death.

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Photos:Who's who in Jackson trial

Key players in Jackson wrongful death trial – Dr. Conrad Murray: He was Michael Jackson's personal physician in the two months before his death, giving him nightly infusions of the surgical anesthetic that the coroner ruled led to his death. Murray, who is appealing his involuntary manslaughter conviction, has sworn that he would invoke his Fifth Amendment protection from self-incrimination and refused to testify in the civil trial. There is a chance that Murray will be brought into court from jail to testify outside the presence of the jury to allow the judge to determine if he would be ordered to testify.

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Key players in Jackson wrongful death trial – Joe Jackson: Michael's father, 84, is on the witness list for the trial and may testify. The Jackson family patriarch, who lives in Las Vegas separately from his wife, has suffered several ministrokes in the last year, which some close to him say have affected him.

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Prince Jackson: Michael's oldest son is considered a key witness in the Jacksons' case against AEG Live, since he is expected to testify about what his father told him about the concert promoter in the last days of his life. Prince, who turned 16 in February, is becoming more independent -- he now has a driver's license and jobs.

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Key players in Jackson wrongful death trial – Paris Jackson: Michael's daughter, who turned 15 on April 3, is on the list of witnesses and was questioned by AEG Live lawyers for several hours on March 21 about her father's death. Paris is an outspoken teen who often posts messages to her 1 million-plus Twitter followers.

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Key players in Jackson wrongful death trial – Blanket Jackson: Although AEG Live asked the judge to order Blanket, 11, to sit for a deposition, and he is one of the four plaintiffs suing them, Michael's youngest son will not be a witness in the trial. His doctor submitted a note to the court saying it would be "medically detrimental" to the child.

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Key players in Jackson wrongful death trial – Randy Phillips: He's president of AEG Live, the concert promoter that contracted with Michael Jackson for his "This Is It" comeback shows set to start in London in July 2009. The Jackson lawsuit says Phillips supervised Dr. Conrad Murray's treatment of Jackson in the weeks before his death, making the company liable for damages. E-mails between Phillips and other executives showed they were worried about Jackson's missed rehearsals and sought Murray's help getting him ready.

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Key players in Jackson wrongful death trial – Kevin Boyle: The Los Angeles personal injury lawyer is leading the Jackson team of at least six attorneys in the wrongful death suit against AEG Live. One of his notable cases was a large settlement with Boeing on behalf of two soldiers injured when their helicopter malfunctioned and crashed in Iraq.

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Key players in Jackson wrongful death trial – Perry Sanders, Jr.: Katherine Jackson's personal lawyer is helping steer the Jackson matriarch through her relations with her son's estate, probate court and the wrongful death suit. He is also known for representing the family of Biggie Smalls in their suit against the city of Los Angeles over the rapper's death investigation.

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Key players in Jackson wrongful death trial – Marvin Putnam: He's the lead lawyer for AEG Live, defending against the wrongful death suit. The primary focus of his legal practice is "media in defense of their First Amendment rights," according to his official biography.

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Key players in Jackson wrongful death trial – Philip Anschutz: The billionaire owner of AEG, parent company of AEG Live, is on the Jacksons' witness list. He is the force behind the effort to build a football stadium in downtown Los Angeles to lure a National Football League team to the city. He recently pulled his company off the market after trying to sell it for $8 billion.

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Key players in Jackson wrongful death trial – Tim Leiweke: He was recently fired as AEG's president as Philip Anschutz announced he was taking a more active role in the company. The Jackson lawyers say Leiweke's e-mail exchanges with executives under him concerning Michael Jackson's health are important evidence in their case.

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Key players in Jackson wrongful death trial – Paul Gongaware: The AEG Live co-CEO worked closely with Michael Jackson as he prepared for his comeback concerts. He testified at Dr. Conrad Murray's criminal trial that he contacted the physician and negotiated his hiring at the request of Jackson. AEG lawyers say it was Jackson who chose, hired and supervised Murray. Gongaware knew Jackson well, having been tour manager for the singer in previous years.

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Key players in Jackson wrongful death trial – John Branca: He's one of two executors of Michael Jackson's estate. Branca was Jackson's lawyer until about seven years before his death. He said Jackson rehired him just weeks before he died.

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Despite these "mistakes," Trell called the CFO "a very detailed-oriented guy."

Jackson's mother and children are suing AEG Live, contending the concert promoter is liable in the singer's death because its executives negligently hired, retained or supervised Dr. Murray, who was convicted of involuntary manslaughter.

The promoters ignored a series of red flags that should have warned them Jackson was in danger as he was pressured to get ready for his comeback concerts, the Jackson lawsuit claims.

AEG Live lawyers counter that it was Jackson who chose, hired and supervised Murray, and that he was responsible for his own bad decisions. Its executives could not be expected to know Murray was using the surgical anesthetic propofol, the drug the coroner ruled killed Jackson, to treat his insomnia, they argue.

The budget terminology could be key in the jury's decision on AEG's liability, since production costs were the promoter's responsibility, while advances were basically loans to Jackson. The revelation that the doctor's fees were designated as production contradicts the defense that AEG lead lawyer Marvin Putnam shared with CNN before the trial.

AEG Live's role with Murray was only to "forward" money owed to him by Jackson, just as a patient would use his "MasterCard," Putnam said. "If you go to your doctor and you pay with a credit card, obviously, MasterCard in that instance, depending on your credit card, is providing the money to that doctor for services until you pay it back. Now, are you telling them MasterCard in some measure in that instance, did MasterCard hire the doctor or did you? Well, clearly you did. I think the analogy works in this instance."

The doctor signed the contract prepared by AEG lawyers and sent it back to the company a day before Jackson's death. The company argues it was not an executed contract because their executives and Michael Jackson never signed it.

The Jackson lawyers argue that e-mails, budget documents and the fact that the doctor was already working for two months showed a binding agreement between AEG and Murray.

Panish, speaking outside of the courtroom Friday, said he would also ask Trell about AEG's insurance claim, which he said his team recently discovered was filed with Lloyds of London on June 25, 2009, hours after Jackson was pronounced dead at UCLA Medical Center.

That revelation may not relate to the heart of the wrongful death lawsuit against Michael Jackson's last concert promoter, but Jackson lawyers hope it could sway jurors to see AEG Live executives as motivated by money over the pop icon's needs.

A Lloyds of London underwriter later sued AEG, claiming the company failed to disclose information about the pop star's health and drug use. AEG dropped its claim for a $17.5 million insurance policy last year.

The opinion Hom submitted for AEG concluded he saw no red flags that should have alerted the promoter that something was wrong with Murray.

He was asked if AEG Live should have realized something was wrong when Murray initially asked for $5 million a year to work as Jackson's personal physician. "That raised a red flag because of the enormous sum of money," Hom testified.

Hom acknowledged he had not seen many of the documents and depositions in the case, and AEG was considering him for a job as the Rolling Stones tour manager at the same time he was asked to testify.